Much has been made of the uncertainties and contingencies of practice, and of the need for social workers to make more explicit use of formal knowledge in order to reduce this uncertainty. However, we argue that this focus on making certainty out of uncertainty glosses over the ways in which both knowledge and practice often propel practitioners towards early and certain judgements when a position of ‘respectful uncertainty’ might be more appropriate. Facilitating learning that will help social workers to deal with uncertainty raises challenges for social work educators. If they are to equip social workers with the skills to exercise ‘wise judgement under conditions of uncertainty’, they will need to recognize the ways in which both theory and popular knowledge are invoked to make unequivocal knowledge in case formulation. In this paper, we suggest ways in which students can be helped to remain in uncertainty and interrogate their knowledge and case reasoning.